Changes in biochemical indicators of cow’s blood during lactation

The article describes the differences in the biochemical parameters of the blood of Holstein-Friesian and Jersey cows according to the timing of lactation. Biochemical blood parameters of cows of both breeds in the groups were generally within normal limits. However, for some indicators, such as total protein, albumin, y-globulins, cholesterol, ALT and AST, especially in first lactation cows, there are significant differences between the groups and for some of them, reference values are exceeded. The most significant differences in biochemical parameters are observed in cows of the first lactation and basically all of them are a reflection of the state of protein metabolism. By the fourth lactation, blood biochemistry indicators in both breeds are somewhat equalized.